This invention relates to the production of nuclear fuel pellets.
Nuclear fuel pellets may be produced from powdered oxides of uranium, plutonium or thorium, or mixtures of these oxides, by granulation of the powders followed by pressing of the granules into compacts and sintering the compacts. Additives are often mixed with the oxide powders and for a variety of reasons for example, to control the porosity of the sintered pellets, to act as a binder for the compacts or to aid sintering. Additives may also be used to control grain size in the sintered pellets, particularly to increase it, and this is now considered desirable because it increases gas atom diffusion length and, hence, reduces gaseous fission product release from the fuel pellets during irradiation.